Process of manufacture of slabs of compressed cork



EMIL HORNSTEIN, OF VIENNA, AUSTRIA.

rRocEss or MANUFACTURE oi SLABS or COMPRESSED CORK.

No Drawing.

7 (GRANTED UNDER THE PROVISIONS To all whom it may concern:

Be it known that I, Dr. EMTL HORN- STEIN, deputy-manager, subject of theEmperor of Austria, residing at Vienna, VI, Kfistlergasse 7, in thecounty of Lower Austria'and State of Austria, have invented certain newand useful Improvements in Processes of Manufacture of Slabs ofCompressed Cork,'of which the following is a specification.

There is already known a process of manufacture of slabs of compressedcork for facing or coverlng, which process is characterized' bypressingin a mould granulated intosuitably thin plates.

cork that has been steamed or moistened with water, whereby there .isproduced a compressed cork slab, which is dried in the mould by"warming, and is thereupon sawn This process has, however, a whole seriesof serious disadvantages. In order to obtain the'requisite compactnessin the structure of the final product, the slab of, compressed cork hasto be compressed with very great force, whereby the subsequent dryingprocess is rendered difficult, since. the compact block, being a badconductor, must be very highly heated from the outside if the heat is topenetrate to the inner part. In this process, the outer edges of theslab are heated to such an extent that the cork substance in partundergoes chemical changes, whereby it assumes uneven colouring, thisoccurring even at a time at which the heat has not yet penetrated to theinterior sufficiently to drive off the humidity; Undersuchcircumstances, there could be no hope of obtaining a constant quality ofthe final product. Moreover, the

' cutting up of adried slab was not always possible in alve'neermachine, on account of its brittleness, but could only. be effected bysawing, so that, as may easily be seen, there was a great deal of waste,which, in View of the comparatively small thickness of the slabs to beproduced, often amounted to 50%. In addition to that in the slabs thusobtained, an evenly close-grained and evenly coloured surface could notbe produced at all; i

' Another method of manufacture of these plates is as follows:

, They are separately produced in suitable moulds, by compressing thenecessary quanany of cork. This prccess, however, has the Specificationof Letters Patent. Patented F b. 21 192% Application filed July 13,1914. Serial No. 850,626.

01? THE ACT OF MARCH 3, 1 921, 41 STAT. L, 1313.)

disadvantage that, even though it might be considered as technicallymore perfect, it is economically less advantageous, as the manipulationrequired is much too expensive and too intricate. In order to improvethis method economically, the slabs of cork were also made of differentqualities of cork, the bottom of the mould being first covered with athin layer of the best cork substance, and coarser and therefore cheapercork being then thrown on to this first layer, so that when compressionhad been effected, a slab was obtained having a compressed surface ofgood cork. Apart from the fact that these expedients resulted in only avery slight increase in the economic value of the intricate process, theproducts obtained had moreover the disadvantage that, as soon as thethin surface layer was worn through, the inferior cork was ,exposed, andthe possibility of employing lthe slab any longer was doubtful.

All the disadvantages mentioned above are avoided in the presentinvention. 'This processis as follows: A suitable number of thin layersobtained by dividing aslab of the compressed cork produced by lowpressure and by-a subsequent drying out, are placed one upon the other,and this pile subjected to higher pressure than that employed for makingthe original slab. The compressed slabs thus obtained are then dried byheat, there being two ways of doing this, drying operations areconducted at a low temperature in order to avoid changes in the corksubstance, the separate layers are stuck togetherby a suitable bindingsubstance. If higher temperatures are employed, the binding substance isnot neces sary, as the products of distillation, given off by the corksubstance at high temperatures, will effect the junction of the separatelayers. y

This process is distinguished from that hereinbefore referredto,principally by the fact that the primary compressed cork slabs aredivided into thinlayers, it being possible to effect this without anywaste and without much difficulty, on a veneer machine. As many of thethin layers thus obtained are placed one upon the other as are necessaryfor the production of the desired slabs, and if necessary, these layersprocess according to the i of heat.

are connected together by a binding substance, such as for mstancecasein-resin cement, or any other waterproof cement. The slabs obtainedby the compression of these piles possess-so little: thickness, thatthey may be simply dried by a moderate amount Unlike those employedinother known processes, the moulds need not be closed on all sides, butonly a top and a bottom piece are required, between which the pile ofcork slabs is placed; the advan- ,-tage thus gained being that, sinceall the V the putting of thegranulated cork in the I mould to the finalcompression.

In order to facilitate the compressing, the layers or piles maybesteamed or moistened with water before pressing, whereby they becomemore flexible. The slabs may also'bemade of layers of cork of difierentquality, the front being superior .to the back, in order to maketherproduct cheap. The top, or perhaps the two top layers, may consistof substance of superior quality to the underneath layers and for thispurpose, two different primary compressed cork slabs are produced, inorder to obtain layers of varying quality, which are then suitablyformed into piles. I The steaming or moistening of the cork beforepressing may be limited to the top layer, whether this be of better orthe same substance as the other layers; this top layer thus becomes moreyielding, and when the whole is pressed, is reduced more than the "otherlayers. Another advantage of this is that the cork slab retains moreelasticity, and moreover asthe under layers are less closely pressedtogether, a smaller quantity of cork is required to produce a giventhicki In every case, cork slabs of extreme evenness and greatresistance, with a perfectly smooth surface, are obtained and such slabsmay be so easily-and cheaply produced that they can compete with anywooden facing of goodfquality, and will moreover be superior to the woodby reason of their special physical properties (excellent insulationagainst heat and sound, absolute constancy of volume etc;,) apart fromthe unique aesthetic effect. 7

What I claim is: r

1. Process for manufacturing compact and solid slabs of compressed cork,consisting in forming by pressure a slab of com pressed finely-dividedcork; dividing said slab into thin layers; forming said layers into apile; and subjecting said pile to pressure. 1

2; Process for manufacturing compact and solidslabs of compressedcork,consisting in forming by pressure aslab of compressed finely-dividedcork; dividing said 1 i slab into thin layers; forming said layers intoa pile; causing, said layers tobecome sticky; subjecting said pile topressure; and drying the pile. V v

3. Process for manufacturing compact and solid slabs of compressed cork,consisting in forming a-slab of compressed cork; dividing said slab intothin layers; forming. said layers into a pile; causing said layers bythe action of heat'to become sticky with the products of distillation;subjecting said pile to pressure; and drying the pile; 7

- 4:. Processfor manufacturing compact and solid slabs ofcompressedcork, consisting in forming at low pressure a slab ofcompressed cork; dividing said slab into thin layers; forming saidlayers into a pile; causing said layers to becomesticky subjecting saidpile to the action of a pressure higher than said low, pressure;,anddrying the pile. v

5. Process for manufacturing compact and solid slabs ofcompressed cork,consisting informing a slab of compressedcork;

and solid slabs of compressed cork, 'consisting of the arrangement of anumber of thin independent layers of pressed cork one upon the other,the steaming of said layers, the pressing of said layers in theirsuperposed dividing said slab intolayers; forming said 1 position andthe drying by heat of the.

pressed and compact layers, sub as described. V V

7. Process for manufacturing compact and solid slabs of compressed cork,consisting of the arrangement of a number of'thin independent layers ofpressed cork one upon the other, the steaming of the top independentlayer, the pressing of said layers, in their superposed position and thedrying. by heat of the pressed and compact layers, the top independentslayer being steamed in order to exert greater compression of the saidtop layer during the pressing of the consolidated slab in order toobtain greater elasticity of the cork slab asa whole, sub:-

tantially V stantially as described.

8. Process for manufacturing compact and solid slabs of compressed cork,consisting in forming a slab of compressed cork; dividing said slab intolayers; formingsaid layers into a pile; causing said layers to be: comesticky; subjecting said pile to pressure between top and bottom plateswhile leavted, in order to exert greater compression of ing the sidesfree to permit the escape of the said top layer during the pressing ofmoisture; and drying the pile. the consolidated slab in order to attain15 9. Process for manufacturing compact greater elasticity of the corkslab as a Whole,

and solid slabs of compressed cork consistsubstantially as described.

ing of the arrangement of a number of thin In testimony whereof I afiixmy signature independent layers of pressed cork one upon in presence oftwo Witnesses.

the other, the Wetting of the top independent layer with water, thepressing of said EMIL HORNSTEIN' layers, in their superposed positionand the Witnesses: drying by heat of the pressed and compact AUGUSTFUGGER,

layers, the top independent layer being wet- SIEGFRIED NEUTER.

